Setting The Nr1 Level Adjustment; Setting The Nr2 Time Constant; Noise Blanker; Pre-Amplifier - Kenwood TS-590S Instruction Manual

9 REJECTING INTERFERENCE
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Setting the NR1 Level Adjustment

NR1 uses an adaptive filter to reduce the noise
element from the received signals. When the S/N
ratio is reasonably good in SSB, using NR1 will
improve the S/N further.
While NR1 is ON, you can further adjust the noise
reduction level by pressing and holding [NR (LEV)],
then turning the MULTI/CH control to select the
level from 1 to 10. The default is 5. The level is
saved separately for SSB/FM/AM and CW/FSK.
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Setting the NR2 Time Constant

You can change the correlation time for NR2
(SPAC). When in SSB mode, select the correlation
time that allows you to hear signals with clarity.
When receiving CW, it is best to select the longest
correlation time that allows reliable reception. The
longer the correlation time, the better the S/N ratio.
When NR2 is ON, press and hold [NR (LEV)], then
turn the MULTI/CH control to select the correlation
time from 2 to 20 ms. The default is 20 ms.
Note:
When using Noise Reduction 1 in SSB, FM, or AM
◆
mode, the beat signal is suppressed along with the
normal signal. This is not a malfunction.
Using Noise Reduction 2 in SSB mode may lower the
◆
clarity of signals or induce pulse noise, depending on the
conditions.

NOISE BLANKER

The Noise Blanker is designed to reduce pulse noise
such as that generated by automobile ignitions. The
Noise Blanker does not function in FM mode.
• NB1 performs blanking through an analog circuit.
NB2 performs blanking using DSP.
Press [NB (LEV)] to cycle between Noise Blanker 1,
Noise Blanker 2, and OFF.
• " " or " " appears, depending on which
Noise Blanker is selected.
You can further adjust the Noise Blanker level from
1 to 10. The default level is 6. Press and hold [NB
(LEV)], then turn the MULTI/CH control to adjust the
Noise Blanker level.
• "NB LV." and the current level appear on the
sub-display.
Note:
The Noise Blanker is available only for SSB, CW, FSK, and
◆
AM modes.
Increasing the Noise Blanker level degrades the
◆
intermodulation characteristics of the transceiver.
For effective Noise Blanker operation, experiment with both
◆
NB1 and NB2 on each band.
When using Noise Blanker 2 and a CW signal is received,
◆
there are times when the received signal may be distorted.
This is not a malfunction.
40

PRE-AMPLIFIER

Switching the pre-amplifier OFF may help reduce
interference from adjacent frequencies.
Press [PRE (ANT 1/2)] to toggle the pre-amplifier ON
and OFF.
• " " appears when this function is ON.
The ON/ OFF setting will be automatically stored in
the current band. Each time you select the same
band, the same setting will be automatically selected
The frequency range of each band is provided in the
table below (under "ATTENUATOR").

ATTENUATOR

The Attenuator reduces the level of received
signals. This function is useful when there is strong
interference from adjacent frequencies.
Press [ATT (RX ANT)] to toggle the attenuator ON
and OFF.
• " " appears when this function is ON.
The ON/ OFF setting will be automatically stored
in the current band. Each time you select the
same frequency band, the attenuator setting will be
automatically recalled. The frequency range of each
band is shown below.
Frequency Pre-amplifier
Band (MHz) (Default)
0.03 ~ 0.522
0.522 ~ 2.5
2.5 ~ 4.1
4.1 ~ 6.9
6.9 ~ 7.5
7.5 ~ 10.5
10.5 ~ 14.5
14.5 ~ 18.5
18.5 ~ 21.5
21.5 ~ 25.5
25.5 ~ 30.0
30.0 ~ 60.0

CW REVERSE (RECEPTION)

This function pivots the BFO from the default position
(USB) to another position (LSB) in CW mode. It is
sometimes effective to remove the interfering signals
from the IF passband by pivoting the BFO.
1 Press [CW/FSK (REV)] until "CW" appears.
2 Press and hold [CW/FSK (REV)].
• "CW" changes to "CWR".
3 To recover the default BFO position, press and
hold [CW/FSK (REV)] again.
• "CWR" changes to "CW".
Attenuator
(Default)
OFF OFF
OFF OFF
OFF OFF
OFF OFF
OFF OFF
ON OFF
ON OFF
ON OFF
ON OFF
ON OFF
ON OFF
ON OFF